Fuel dispensing facilities are in widespread use, providing customers with liquid fuel for various applications. A common fueling transaction, where fuel is dispensed into a vehicle fuel tank, typically proceeds as follows: The customer indicates to the fuel dispenser the type of fuel desired and a payment method. The fuel dispenser authorizes payment and energizes a pump which pumps fuel to the nozzle. The customer places the nozzle into the vehicle fuel tank and pulls the handle of the nozzle to open a valve and dispense the desired amount of fuel.
Fuel dispensing nozzles are often equipped with shutoff mechanisms to stop the flow of fuel if certain trigger conditions occur, such as when the vehicle fuel tank is full. These shutoff mechanisms are meant to prevent fuel spillage. The shutoff mechanism may be associated with an attitude sensing device which is configured to trigger the shutoff mechanism and stop the flow of fuel when the nozzle is angled at or above horizontal—an orientation likely achieved, for example, when the nozzle is removed from the tank while dispensing.
However, current attitude sensing devices frequently trigger the shutoff mechanism when the trigger conditions are not actually present. These unintended valve shutoffs—i.e., nuisance trips—occur for a variety of reasons, one of which is an overly sensitive or faulty attitude sensing device. Therefore, it is desirable to have an attitude sensing device that reliably and predictably triggers the shutoff mechanism when the trigger conditions occur, but minimizes or eliminates the number of unintended nuisance trips.